Organic light-emitting display device and method of manufacturing the same

ABSTRACT

An organic light-emitting display device includes: a substrate; a pixel electrode on the substrate; a pixel defining layer having a first opening exposing a center portion of the pixel electrode; a barrier layer on the pixel defining layer; an intermediate layer including a first common layer, a first emissive layer, and a second common layer sequentially arranged on the pixel electrode, the pixel defining layer, and the barrier layer; and a first opposite electrode covering the intermediate layer. The barrier layer has a second opening that is larger than the first opening and has an undercut structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/288,715, filed Feb. 28, 2019, which claims priority to and thebenefit of Korean Patent Application No. 10-2018-0028268, filed Mar. 9,2018, the entire content of both of which is incorporated herein byreference.

BACKGROUND 1. Field

Aspects of embodiments of the present disclosure relate to an organiclight-emitting display device and a method of manufacturing the same.

2. Description of the Related Art

An organic light-emitting display device includes organic light-emittingelements, each including a hole injection electrode, an electroninjection electrode, and an organic emissive layer interposedtherebetween. The organic light-emitting display device is aself-emissive display device in which excitons are generated when holesinjected from the hole injection electrode and electrons injected fromthe electron injection electrode are combined in the organic emissivelayer, and light is generated as excitons fall from an excited state toa ground state.

Using a fine metal mask (FMM) to deposit the organic emissive layer on asubstrate has drawbacks, such as relatively high manufacturing costs andhigh alignment demands, and as such, alternative deposition techniqueshave been researched.

SUMMARY

Embodiments of the present disclosure include an organic light-emittingdisplay device and a method of manufacturing the same that overcome someof the drawbacks of a fine metal mask and prevent or substantiallyreduce leakage current. However, the aspects and features of the presentdisclosure described herein are exemplary and do not limit the scope ofthe present disclosure. Additional aspects and features of the presentdisclosure will be set forth, in part, in the following description and,in part, will be apparent from the description or may be learned bypractice of the described embodiments.

According to an embodiment, an organic light-emitting display deviceincludes: a substrate; a pixel electrode on the substrate; a pixeldefining layer having a first opening exposing a center portion of thepixel electrode; a barrier layer on the pixel defining layer, thebarrier layer having a second opening that is larger than the firstopening and having an undercut structure; an intermediate layerincluding a first common layer, a first emissive layer, and a secondcommon layer sequentially arranged on the pixel electrode, the pixeldefining layer, and the barrier layer; and a first opposite electrodecovering the intermediate layer.

Portions of the first opposite electrode on the pixel electrode, thepixel defining layer, and the barrier layer may be connected to eachother.

Portions of the second common layer on the pixel electrode, the pixeldefining layer, and the barrier layer may be connected to each other.

Portions of the first emissive layer on the pixel electrode, the pixeldefining layer, and the barrier layer may be connected to each other.

Portions of the first common layer may be disconnected from each otherat a boundary between the pixel defining layer and the barrier layer.

A thickness of the barrier layer may be greater than a thickness of theintermediate layer.

A thickness of the barrier layer may be greater than a thickness of thefirst common layer.

The barrier layer may include a first barrier layer and a second barrierlayer on the first barrier layer, and the second barrier layer may havean undercut structure.

The first opposite electrode may completely cover the intermediatelayer.

The organic light-emitting display device may further include a commonelectrode on the first opposite electrode.

According to another embodiment, an organic light-emitting displaydevice includes: a substrate; a pixel electrode on the substrate; apixel defining layer having a first opening exposing a center portion ofthe pixel electrode, the first opening having an undercut structure; anintermediate layer including a first common layer, a first emissivelayer, and a second common layer sequentially arranged on the pixelelectrode and the pixel defining layer; and a first opposite electrodecovering the intermediate layer.

Portions of the first opposite electrode on the pixel electrode and thepixel defining layer may be connected to each other.

Portions of the first common layer may be disconnected from each otherat a boundary between the pixel defining layer and the pixel electrode.

A thickness of the pixel defining layer may be greater than a thicknessof the first common layer.

According to another embodiment, a method of manufacturing an organiclight-emitting display device includes: forming a plurality of pixelelectrodes on a substrate; forming a pixel defining layer having aplurality of first openings respectively exposing a center portion ofthe plurality of pixel electrodes; forming a barrier layer on the pixeldefining layer and between the plurality of pixel electrodes, thebarrier layer having a plurality of second openings that are larger thancorresponding ones of the first openings and have an undercut structure;forming a first lift-off layer and a first photoresist covering theplurality of pixel electrodes, the pixel defining layer, and the barrierlayer; patterning the first lift-off layer and the first photoresist toform a third opening therein at a position corresponding to a firstpixel electrode from among the plurality of pixel electrodes; forming afirst intermediate layer including a first common layer, a firstemissive layer, and a second common layer in the third opening; forminga first opposite electrode covering the first intermediate layer; andremoving the first lift-off layer and the first photoresist.

A thickness of the pixel defining layer may be greater than a thicknessof the first common layer.

The first lift-off layer may include fluorine.

In the removing of the first lift-off layer and the first photoresist,the first lift-off layer may be removed by using a solvent comprisingfluorine.

The method may further include: forming a second lift-off layer and asecond photoresist after the removing of the first lift-off layer andthe first photoresist; forming a fourth opening in the second lift-offlayer and the second photoresist at a position corresponding to a secondpixel electrode from among the pixel electrodes and at a positiondifferent from the position of the first pixel electrode; forming asecond intermediate layer including a first common layer, a secondemissive layer, and a second common layer in the fourth opening; forminga second opposite electrode covering the second intermediate layer; andremoving the second lift-off layer and the second photoresist.

According to another embodiment, a method of manufacturing an organiclight-emitting display device includes: forming a plurality of pixelelectrodes on a substrate; forming a pixel defining layer having aplurality of first openings respectively exposing a center portion ofthe pixel electrodes and having an undercut structure; forming a firstlift-off layer and a first photoresist covering the pixel electrodes andthe pixel defining layer; forming a third opening in the first lift-offlayer and the first photoresist at a position corresponding to a firstpixel electrode from among the plurality of pixel electrodes; forming afirst intermediate layer including a first common layer, a firstemissive layer, and a second common layer in the third opening; forminga first opposite electrode covering the first intermediate layer; andremoving the first lift-off layer and the first photoresist.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and features of the present disclosure willbecome apparent and more readily appreciated from the followingdescription of example embodiments, taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a schematic cross-sectional view of a portion of an organiclight-emitting display device according to an embodiment of the presentdisclosure;

FIG. 2 is a schematic plan view of some elements of the organiclight-emitting display device shown in FIG. 1 ;

FIG. 3 is a schematic cross-sectional view taken along the line III-IIIof FIG. 2 ;

FIGS. 4A-4F are schematic cross-sectional views of a first unit processfor manufacturing the organic light-emitting display device shown inFIG. 1 according to an embodiment of the present disclosure;

FIGS. 5A-5F are schematic cross-sectional views of a second unit processfor manufacturing the organic light-emitting display device shown inFIG. 1 according to an embodiment of the present disclosure;

FIGS. 6A-6F are schematic cross-sectional views of a third unit processfor manufacturing the organic light-emitting display device according toan embodiment of the present disclosure;

FIG. 7 is a schematic cross-sectional view of a portion of the organiclight-emitting display device including a common electrode formed afterthe third unit process;

FIGS. 8A and 8B are schematic cross-sectional views of a process formanufacturing an organic light-emitting display device according to acomparative example;

FIG. 9 is an enlarged cross-sectional view of the portion IX of FIG. 8B;

FIG. 10 is a schematic cross-sectional view of a portion of an organiclight-emitting display device according to an embodiment of the presentdisclosure;

FIG. 11 is a schematic cross-sectional view of a portion of an organiclight-emitting display device according to an embodiment of the presentdisclosure; and

FIG. 12 is a schematic cross-sectional view of a portion of an organiclight-emitting display device according to an embodiment of the presentdisclosure.

DETAILED DESCRIPTION

Reference will now be made in detail to example embodiments which areillustrated in the accompanying drawings. Like reference numerals referto like elements throughout. In this regard, the presented exampleembodiments may have different forms and should not be construed asbeing limited to the descriptions set forth herein. Accordingly, exampleembodiments are merely described below, by referring to the figures, toexplain aspects and features of the present description. As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items. Expressions, such as “at least one of”,when preceding a list of elements, modify the entire list of elementsand do not modify the individual elements of the list. Further, the useof “may” when describing embodiments of the present invention relates to“one or more embodiments of the present invention.” Also, the term“exemplary” is intended to refer to an example or illustration. As usedherein, the terms “use,” “using,” and “used” may be consideredsynonymous with the terms “utilize,” “utilizing,” and “utilized,”respectively.

As the disclosure allows for various changes and numerous embodiments,example embodiments will be illustrated in the drawings and described indetail in the written description. Aspects, features, and a method ofachieving the same will be specified with reference to the exampleembodiments described below in detail together with the attacheddrawings. However, the present disclosure may have different forms andshould not be construed as being limited to the descriptions and exampleembodiments set forth herein.

It will be understood that although the terms “first,” “second,” etc.may be used herein to describe various components, these componentsshould not be limited by these terms. These terms are only used todistinguish one component from another. Singular expressions, unlessdefined otherwise in the context, include plural expressions. In theembodiments below, it will be further understood that the terms“comprise,” “include,” and/or “have” used herein specify the presence ofstated features or components but do not preclude the presence oraddition of one or more other features or components.

It will be understood that when a component, such as a layer, a film, aregion, or a plate, is referred to as being “on” another component, thecomponent may be “directly on” the other component or interveningcomponents may also be present.

Also, for convenience of explanation, sizes of components in thedrawings may be exaggerated for convenience of explanation. Becausesizes and thicknesses of components in the drawings may be arbitrarilyillustrated for convenience of explanation, the following embodimentsare not limited thereto.

When an embodiment is implementable in another manner, a process ordermay be implemented differently from how it is described. For example,two processes that are consecutively described may be performedconcurrently or substantially simultaneously performed or may beperformed in an opposite order to the described order.

FIG. 1 is a schematic cross-sectional view of a pixel of an organiclight-emitting display device 1 according to an embodiment of thepresent disclosure.

Referring to FIG. 1 , the organic light-emitting display device 1includes a first pixel electrode 101 arranged on a substrate 100, apixel defining layer 110 having a first opening OP1 exposing a centerportion of the first pixel electrode 101, a barrier layer 120 arrangedon the pixel defining layer 110 and having a second opening OP2 that islarger than the first opening OP1 and has an undercut structure, a firstintermediate layer 130-1 arranged on the first pixel electrode 101, thepixel defining layer 110, and the barrier layer 120, a first oppositeelectrode 141 covering the first intermediate layer 130-1, and a commonelectrode 150 arranged on (e.g., in direct contact with) the firstopposite electrode 141.

The substrate 100 may be formed of various suitable materials. Forexample, the substrate 100 may be formed of glass, metal, plastic, orthe like. Plastics having excellent heat resistance and durability, suchas polyimide, polyethylene naphthalate, polyethylene terephthalate,polyarylate, polycarbonate, polyetherimide or polyethersulfone, may beused to form the substrate 100.

The first pixel electrode 101 may be a hole injection electrode and maybe formed of a material having a high work function. The first pixelelectrode 101 may include a transparent conductive oxide material orcomponent. For example, the first pixel electrode 101 may include atleast one selected from the group including an indium tin oxide, anindium zinc oxide, a zinc oxide, an indium oxide, an indium galliumoxide, and an aluminum zinc oxide. The first pixel electrode 101 may bea single layer or a plurality of layers and may further include a metal,such as silver (Ag), aluminum (Al), magnesium (Mg), lithium (Li), andcalcium (Ca), and/or an alloy of these metals. The first pixel electrode101 is arranged in the form of an island.

The pixel defining layer 110 has the first opening OP1, which exposes acenter portion of the first pixel electrode 101, and covers an edge ofthe first pixel electrode 101.

When low-voltage power is applied through the common electrode 150 andthe first opposite electrode 141, which will be further described later,an electrical field may be concentrated at an end portion of the firstpixel electrode 101 and an electric short may occur during driving. Thepixel defining layer 110 may cover the edge of the first pixel electrode101 to prevent or substantially reduce a concentration of an electricfield at the edge of the first pixel electrode 101.

The pixel defining layer 110 may be formed of an organic insulatinglayer including at least one of an acrylic polymer, an imide polymer, anaryl ether polymer, an amide polymer, a fluorine polymer, a phenolpolymer, a p-xylene polymer, and a vinyl alcohol polymer.

The barrier layer 120 having the second opening OP2, which is largerthan the first opening OP1 in the pixel defining layer 110, is arrangedon the pixel defining layer 110.

In the illustrated embodiment, the barrier layer 120 includes a firstbarrier layer 121 and a second barrier layer 122 having an undercutstructure. The undercut structure refers to a structure in which an edgeof a top surface of the second barrier layer 122 protrudes from an edgeof a bottom surface thereof with respect to an imaginary reference lineperpendicular to the substrate 100.

The first barrier layer 121 and the second barrier layer 122 may beformed of an inorganic insulating film or an organic insulating film. Inthe illustrated embodiment, a total thickness D1 of the barrier layer120 including the first barrier layer 121 and the second barrier layer122 is greater than a total thickness D130-1 of the first intermediatelayer 130-1.

The first intermediate layer 130-1 is arranged on the first pixelelectrode 101, the pixel defining layer 110, and the barrier layer 120.The first intermediate layer 130-1 may include a first common layer 131,a first emissive layer 132, and a second common layer 135.

Although the first common layer 131 is illustrated as being a singlelayer in FIG. 1 , the present disclosure is not limited thereto. Thefirst common layer 131 may include a hole injection layer and/or a holetransport layer and may further include other suitable functionallayers, such as a hole injection layer, a hole transport layer, and/orthe like. The first common layer 131 is arranged in an island shape.

In the illustrated embodiment, the first common layer 131 isdisconnected at (e.g., is disconnected from itself) a boundary betweenthe barrier layer 120 and the pixel defining layer 110 (e.g., a portionof the first common layer 131 on the barrier layer 120 and a portion ofthe first common layer 131 on the pixel defining layer 110 aredisconnected or separated from each other). An end portion (e.g., adisconnected portion) of the first common layer 131 and the firstopposite electrode 141 contact each other on the second barrier layer122. When the first common layer 131 is disconnected at the boundarybetween the barrier layer 120 and the pixel defining layer 110,electrons injected into the first common layer 131 by the first oppositeelectrode 141 along a contact surface between the first oppositeelectrode 141 and the first common layer 131 on the second barrier layer122 do not flow to the first pixel electrode 101 through the pixeldefining layer 110. Accordingly, leakage current of an organiclight-emitting element may be prevented or substantially reduced.

The first emissive layer 132 is arranged on the first common layer 131.The first emissive layer 132 may include a low molecular weight materialand/or a polymer material. The first emissive layer 132 may includevarious suitable organic materials, such as copper phthalocyanine(CuPc), N,N′-di(naphthalene-1-yl)-N,N′-diphenyl-benzidine (NPB),tris-8-hydroxyquinoline aluminum (Alq3), and/or the like. The firstemissive layer 132 may include other organic materials, such aspoly-phenylene vinylene (PPV) or polyfluorene. The first emissive layer132 is arranged in an island shape.

In the illustrated embodiment, the first emissive layer 132 isdisconnected at the boundary between the barrier layer 120 and the pixeldefining layer 110 (e.g., a portion of the first emissive layer 132 onthe barrier layer 120 is disconnected from a portion of the firstemissive layer 132 on the pixel defining layer 110). Because the firstemissive layer 132 is disconnected from itself, the effect of thedisconnection of the first common layer 131 described above is increased(e.g., doubled).

The second common layer 135 is arranged on the first emissive layer 132.Although the second common layer 135 is illustrated as being a singlelayer in FIG. 1 , the present disclosure is not limited thereto. Thesecond common layer 135 may include an electron transport layer and/oran electron injection layer and may further include suitable functionallayers other than the electron injection layer or the electron transportlayer. The second common layer 135 is arranged in an island shape.

In the illustrated embodiment, the second common layer 135 isdisconnected at the boundary between the barrier layer 120 and the pixeldefining layer 110 (e.g., a portion of the second common layer 135 onthe barrier layer 120 is disconnected from a portion of the secondcommon layer 135 on the pixel defining layer 110). Because the secondcommon layer 135 is disconnected from itself, the effect of thedisconnection of the first common layer 131 described above is increased(e.g., doubled).

The first opposite electrode 141 is arranged on the second common layer135 in an island shape.

The first opposite electrode 141 may be a semi-transmissive electrode ora transmissive electrode and may be formed of a metal in the form of athin film. The first opposite electrode 141 may have a thickness in arange of several nanometers to several tens of nanometers to transmitlight. For example, the first opposite electrode 141 may include Ag, Al,Mg, Li, Ca, Cu, lithium fluoride/calcium (LiF/Ca), lithiumfluoride/aluminum (LiF/Al), and/or a compound thereof (e.g., MgAg orCaAg). The first opposite electrode 141 may further include atransparent conductive material, such as ITO, IZO, ZnO, In₂O₃, IGO,and/or AZO.

In the illustrated embodiment, the first opposite electrode 141 isconnected at (e.g., is connected to itself at or is continuous across)the boundary between the barrier layer 120 and the pixel defining layer110 (e.g., the first opposite electrode 141 is not disconnected fromitself at the boundary between the barrier layer 120 and the pixeldefining layer 110). In addition, the first opposite electrode 141 isarranged to completely cover the first intermediate layer 130-1, whichis arranged on the first pixel electrode 101, the pixel defining layer110, and the barrier layer 120.

The common electrode 150 is arranged on the first opposite electrode141. The common electrode 150 is not arranged in the form of an islandin each pixel like the first opposite electrode 141 but has asingle-body form commonly (e.g., continuously) arranged over a pluralityof pixels (e.g., a single, continuous common electrode 150 may be formedover all of the pixels).

The common electrode 150 is configured to transfer a low voltage from apower supply wiring to the first pixel electrode 101 through the firstopposite electrode 141, which is in direct contact with the commonelectrode 150. When a driving voltage is transmitted from a driving thinfilm transistor connected to the first pixel electrode 101 and reaches athreshold voltage, excitons are generated in the first emissive layer132 and emit light as they fall from an excited state to a ground state.

Ideally, current does not flow through the organic light-emittingelement before the driving voltage reaches the threshold voltage.However, in a conventional organic light-emitting display device,electrons may flow from the first opposite electrode 141 to the firstcommon layer 131 at an area where the first opposite electrode 141 andthe first common layer 131 are in direct contact with each other, andthese electrons may flow to the first pixel electrode 101 and generate aleakage current. However, according to embodiments of the presentdisclosure, the first common layer 131 is disconnected at the boundarybetween the barrier layer 120 and the pixel defining layer 110, andthus, electrons from the first opposite electrode 141 do not flow to thefirst common layer 131. Accordingly, leakage current may be prevented orsubstantially reduced.

Hereinafter, a method of manufacturing the organic light-emittingdisplay device 1 shown in FIG. 1 will be described with reference toFIGS. 2-7 .

FIG. 2 is a schematic plan view of some elements of the organiclight-emitting display device 1. FIG. 3 is a schematic cross-sectionalview taken along the line III-III of FIG. 2 . FIGS. 4A-4F are schematiccross-sectional views of a first unit process for manufacturing theorganic light-emitting display device 1 according to an embodiment ofthe present disclosure. FIGS. 5A-5F are schematic cross-sectional viewsof a second unit process for manufacturing the organic light-emittingdisplay device 1 according to an embodiment of the present disclosure.FIGS. 6A-6F are schematic cross-sectional views of a third unit processfor manufacturing the organic light-emitting display device 1 accordingto an embodiment of the present disclosure. FIG. 7 is a schematiccross-sectional view of a pixel of the organic light-emitting displaypanel including a common electrode formed after the third unit process.

Referring to FIGS. 2 and 3 , the first pixel electrode 101, a secondpixel electrode 102, and a third pixel electrode 103 are formed on thesubstrate 100.

A buffer layer may be further formed on the substrate 100 (e.g., may beformed on the substrate 100 below the first through third pixelelectrodes 101, 102, and 103) to provide a relatively smooth surface andto block penetration of impurities into the display device. For example,the buffer layer may be formed of silicon nitride, silicon oxide, and/orthe like, as a single layer or a plurality of layers.

The first through third pixel electrodes 101, 102, and 103 are holeinjection electrodes as described above and may be formed of a materialhaving a high work function.

First through third thin film transistors may be arranged between thesubstrate 100 and the first through third pixel electrodes 101, 102, and103 and are respectively electrically connected to the first throughthird pixel electrodes 101, 102, and 103.

The pixel defining layer 110 is formed to cover edges of the firstthrough third pixel electrodes 101, 102 and 103 and to have firstopenings OP1 that expose center portions of the first through thirdpixel electrodes 101, 102 and 103. While the first openings OP1illustrated in FIG. 3 have the same size, this is an example, and thesizes of the first openings OP1 may vary by pixel.

The barrier layer 120 including the first barrier layer 121 and thesecond barrier layer 122 is arranged on the pixel defining layer 110.The second barrier layer 122 has second openings OP2 that are largerthan the corresponding first openings OP1 in the pixel defining layer110. For example, a width W120 of the barrier layer 120 between twoadjacent second openings OP2 is smaller than a width W110 of the pixeldefining layer 110 between two adjacent first openings OP1.

The second barrier layer 122 is formed to have an undercut structure(e.g., an undercut-shaped structure). The first barrier layer 121 andthe second barrier layer 122 may be formed of an inorganic insulatingfilm or an organic insulating film, and the second openings OP2 in thesecond barrier layer 122 may be formed to have the undercut structure bycontrolling materials and etching conditions of the second barrier layer122. The undercut structure affects deposition conditions of firstthrough third intermediate layers 130-1, 130-2, and 130-3 and firstthrough third opposite electrodes 141, 142, and 143 formed later.

Referring to FIG. 4A, a first lift-off layer 161 and a first photoresist171 are sequentially formed on the structure shown in FIG. 3 .

The first lift-off layer 161 includes a fluoropolymer. The fluoropolymerincluded in the first lift-off layer 161 may be formed of a polymerhaving a fluorine content in a range of about 20 wt % to about 60 wt %.For example, the fluoropolymer included in the first lift-off layer 161may include at least one selected from the group consisting ofpolytetrafluoroethylene, polychlorotrifluoroethylene,polydichlorodifluoroethylene, a copolymer of chlorotrifluoroethylene anddichlorodifluoroethylene, a copolymer of tetrafluoroethylene andperfluoroalkylvinylether, a copolymer of chlorotrifluoroethylene andperfluoroalkylvinylether, a copolymer of tetrafluoroethylene andperfluoroalkylvinylether, a copolymer of perfluoroalkyl vinyl ether andperfluoroalkyl vinyl ether, a copolymer of tetrafluoroethylene andperfluoroalkyl vinyl ether, or a copolymer of chlorotrifluoroethyleneand perfluoroalkyl vinyl ether. The first lift-off layer 161 may beformed by using a coating method, a printing method, a depositionmethod, or the like.

The first photoresist 171 is formed on the first lift-off layer 161. Thefirst photoresist 171 is exposed (e.g., developed) through a lighttransmitting portion M11 of a first photomask M1 at a positioncorresponding to the first pixel electrode 101. The first photomask M1includes the light transmitting portion M11 and a light blocking portionM12.

Referring to FIG. 4B, the first photoresist 171 is developed. The firstphotoresist 171 may be either a positive type or a negative type.Hereinafter, a positive type photoresist will be described as anexample. A first portion 171-1 of the photoresist 170 corresponding tothe first pixel electrode 101 and the light transmitting portion M11 ofthe first photomask M1 is removed from the first photoresist 171 duringthe exposure (e.g., during the development) and the remaining portion(e.g., a second portion 171-2 of the photoresist 170) remains.

Referring to FIG. 4C, the first lift-off layer 161 is etched accordingto a pattern of the first portion 171-1 of the first photoresist 171shown in FIG. 4B by using the photoresist 171 as an etching mask.

The first lift-off layer 161 includes a fluoropolymer, and thus, asolvent capable of etching the fluoropolymer is used as an etchingsolution. A first solvent may include hydrofluoroether. Hydrofluoroetheris an electrochemically stable material due to its low interaction withother materials and is environmentally stable due to its low globalwarming potential and low toxicity.

A portion of the first lift-off layer 161 at a position corresponding tothe first portion 171-1, that is, a portion of the first lift-off layer161 formed on the first pixel electrode 101, is etched by the etchingprocess. When the first lift-off layer 161 is etched, the first solventincluding fluorine forms a first undercut profile UC1 under the firstportion 171-1 of the first photoresist 171 (e.g., under an interface ofthe first portion 171-1 of the first photoresist 171 and the firstlift-off layer 161).

Referring to FIG. 4D, the first intermediate layer 130-1 including thefirst common layer 131, the first emissive layer 132, and the secondcommon layer 135 is formed on the structure shown in FIG. 4C.

The first common layer 131, the first emissive layer 132, and the secondcommon layer 135 are each formed by vacuum deposition. The first commonlayer 131, the first emissive layer 132, and the second common layer 135are sequentially formed by controlling an angle of incidence ofdeposition of a deposition material discharged from a deposition sourcetoward the substrate 100.

The first common layer 131, the first emissive layer 132, and the secondcommon layer 135 are sequentially stacked on the first pixel electrode101, the pixel defining layer 110, and the barrier layer 120. The firstcommon layer 131, the first emissive layer 132, and the second commonlayer 135 are also stacked on the first photoresist 171.

Because the first lift-off layer 161 and the first photoresist 171,which together form the undercut structure UC1, function as a mask, thefirst common layer 131, the first emissive layer 132, and the secondcommon layer 135 are not uniformly deposited but are deposited with agradually decreasing thickness towards end portions thereof on thesecond barrier layer 122.

In the illustrated embodiment, the first common layer 131, the firstemissive layer 132, and the second common layer 135 are disconnectedfrom themselves at a boundary between the barrier layer 120 and thepixel defining layer 110.

Referring to FIG. 4E, the first opposite electrode 141 is formed byvacuum deposition on the structure shown in FIG. 4D.

The first opposite electrode 141 is deposited to completely cover thefirst intermediate layer 130-1, which includes the first common layer131, the first emissive layer 132, and the second common layer 135, byadjusting an angle of incidence of deposition at which a depositionmaterial discharged from a deposition source is incident toward thesubstrate 100. For example, the first opposite electrode 141 is formedto have a greater area than the first intermediate layer 130-1. Asdescribed above, because the first opposite electrode 141 completelycovers the first intermediate layer 130-1, damage to the firstintermediate layer 130-1, including the first emissive layer 132, due tothe first solvent used in a lift-off operation, which will be furtherdescribed later, may be prevented or substantially reduced.

Referring to FIG. 4F, the lift-off operation is performed to thestructure of FIG. 4D.

The first lift-off layer 161 includes a fluoropolymer, and thus, thefirst lift-off layer 161 is removed by using a second solvent includingfluorine. Because the lift-off operation is performed after forming thefirst intermediate layer 130-1, which includes the first emissive layer132, a material having low reactivity with the first intermediate layer130-1 may be used as the second solvent. The second solvent may includehydrofluoroether, similar to the first solvent.

After the lift-off operation, the first intermediate layer 130-1 and thefirst opposite electrode 141 are left as patterns on the first pixelelectrode 101, the pixel defining layer 110, and the barrier layer 120.

After performing the above-described first unit process, a second unitprocess including forming a second emissive layer 133 that emits lighthaving a different color from the first emissive layer 132 is performedin an area where the second pixel electrode 102 is located. Likereference numerals may represent like structures, and the belowdescription of the second unit process will primarily focus ondifferences from the above-described first unit process.

Referring to FIG. 5A, a second lift-off layer 162 and a secondphotoresist 172 are sequentially formed on the structure shown in FIG.4F.

The second lift-off layer 162 includes a fluoropolymer and may be formedof a same or a substantially similar material as the first lift-offlayer 161 described above.

The second photoresist 172 is formed on the second lift-off layer 162,and a portion of the second photoresist 172 at a position correspondingto the second pixel electrode 102 is exposed through alight-transmitting portion M21 of a second photomask M2, which includesthe light-transmitting portion M21 and a light-blocking portion M22.

Referring to FIG. 5B, the second photoresist 172 is developed. After thesecond photoresist 172 is developed, a first portion 172-1 correspondingto the second pixel electrode 102 is removed from the second pixelelectrode 102, and the remaining portion (e.g., a second portion 172-2)remains.

Referring to FIG. 5C, the second lift-off layer 162 is etched by using apattern of the first portion 172-1 of the second photoresist 172 of FIG.5B as an etching mask.

The second lift-off layer 162 may be etched by using the first solventincluding fluorine. The second lift-off layer 162 formed at a positioncorresponding to the first portion 172-1, that is, a portion of thesecond lift-off layer 162 formed on the second pixel electrode 102 isetched by an etching process. When the second lift-off layer 162 isetched, the first solvent including fluorine forms a second undercutprofile UC2 under the first portion 172-1 of the second photoresist 172(e.g., under an interface of the first portion 172-1 of the secondphotoresist 172 and the second lift-off layer 162).

Referring to FIG. 5D, the second intermediate layer 130-2, whichincludes the first common layer 131, the second emissive layer 133, andthe second common layer 135, is formed on the structure shown in FIG.5C.

The first common layer 131, the second emissive layer 133, and thesecond common layer 135 are each formed by vacuum deposition. The firstcommon layer 131, the second emissive layer 133, and the second commonlayer 135 are sequentially formed by controlling an angle of incidenceof deposition of a deposition material discharged from a depositionsource toward the substrate 100.

The first common layer 131, the second emissive layer 133, and thesecond common layer 135 are sequentially stacked on the second pixelelectrode 102, the pixel defining layer 110, and the barrier layer 120.The first common layer 131, the second emissive layer 133, and thesecond common layer 135 are also stacked on the second photoresist 172.

Because the second lift-off layer 162 and the second photoresist 172,which together form the second undercut structure UC2, function as amask, the first common layer 131, the second emissive layer 133, and thesecond common layer 135 are not uniformly deposited but are depositedwith a gradually decreasing thickness towards end portions thereof onthe second barrier layer 122.

In the illustrated embodiment, the first common layer 131, the secondemissive layer 133, and the second common layer 135 are formed to bedisconnected from themselves at the boundary between the barrier layer120 and the pixel defining layer 110.

Referring to FIG. 5E, the second opposite electrode 142 is formed byvacuum deposition on the structure shown in FIG. 5D.

The second opposite electrode 142 is deposited to completely cover thesecond intermediate layer 130-2, which includes the first common layer131, the second emissive layer 133, and the second common layer 135, byadjusting an angle of deposition and incidence at which a depositionmaterial discharged from a deposition source is incident toward thesubstrate 100. For example, the second opposite electrode 142 is formedto have a larger area than the second intermediate layer 130-2. Asdescribed above, because the second opposite electrode 142 completelycovers the second intermediate layer 130-2, damage to the secondintermediate layer 130-2, which includes the second emissive layer 133,due to the first solvent used in a lift-off operation, which will befurther described later, may be prevented or substantially reduced.

Referring to FIG. 5F, the lift-off operation is performed on thestructure shown in FIG. 5D.

The second lift-off layer 162 is removed by using the second solventincluding fluorine.

After the lift-off operation, the second intermediate layer 130-2 andthe second opposite electrode 142 are left as patterns on the secondpixel electrode 102, the pixel defining layer 110, and the barrier layer120, together with the patterns of the first intermediate layer 130-1and the first opposite electrode 141 formed in the first unit process.

After performing the second unit process described above, a third unitprocess of forming a third emissive layer 134 that emits light having adifferent color from the first emissive layer 132 and the secondemissive layer 133 is performed in an area where the third pixelelectrode 103 is located. Like reference numerals may represent likestructures, and the description of the third unit process will primarilyfocus on differences from the above-described first unit process.

Referring to FIG. 6A, a third lift-off layer 163 and a third photoresist173 are sequentially formed on the structure shown in FIG. 5F.

The third lift-off layer 163 includes a fluoropolymer and may be formedof a same or a substantially similar material as the first lift-offlayer 161 described above.

The third photoresist 173 is formed on the third lift-off layer 163, anda portion of the third photoresist 173 at a position corresponding tothe third pixel electrode 103 is exposed through a light-transmittingportion M31 of a third photomask M3, which includes thelight-transmitting portion M31 and a light-blocking portion M32.

Referring to FIG. 6B, the third photoresist 173 is developed. After thethird photoresist 173 is developed, a first portion 173-1 correspondingto third pixel electrode 103 is removed from the third photoresist 173,and the remaining portion (e.g., a second portion 173-2) remains.

Referring to FIG. 6C, the third lift-off layer 163 is etched by using apattern of the first portion 173-1 of the third photoresist 173 shown inFIG. 6B as an etching mask.

The third lift-off layer 163 may be etched by using the first solventincluding fluorine. The third lift-off layer 163 formed at a positioncorresponding to the first portion 173-1, that is, a portion of thethird lift-off layer 163 formed on the third pixel electrode 103, isetched by an etching process. When the third lift-off layer 163 isetched, the first solvent including fluorine forms a third undercutprofile UC3 under the first portion 173-1 of the third photoresist 173(e.g., under an interface of the first portion 173-1 of the thirdphotoresist 173 and the third lift-off layer 163).

Referring to FIG. 6D, the third intermediate layer 130-3, which includesthe first common layer 131, the third emissive layer 134, and the secondcommon layer 135, is formed on the structure shown in FIG. 6C.

The first common layer 131, the third emissive layer 134, and the secondcommon layer 135 are each formed by vacuum deposition. The first commonlayer 131, the third emissive layer 134, and the second common layer 135are sequentially formed by controlling an angle of incidence ofdeposition of a deposition material discharged from a deposition sourcetoward the substrate 100.

The first common layer 131, the third emissive layer 134, and the secondcommon layer 135 are sequentially stacked on the third pixel electrode103, the pixel defining layer 110, and the barrier layer 120. The firstcommon layer 131, the third emissive layer 134, and the second commonlayer 135 are also stacked on the third photoresist 173.

Because the third lift-off layer 163 and the third photoresist 173,which together form the third undercut structure UC3, function as amask, the first common layer 131, the third emissive layer 134, and thesecond common layer 135 are not uniformly deposited but are depositedwith a gradually decreasing thickness towards end portions thereof onthe second barrier layer 122.

The first common layer 131, the third emissive layer 134, and the secondcommon layer 135 are formed to be disconnected from themselves at theboundary between the barrier layer 120 and the pixel defining layer 110.

Referring to FIG. 6E, a third opposite electrode 143 is formed by vacuumdeposition on the structure shown in FIG. 6D.

The third opposite electrode 143 is deposited to completely cover thethird intermediate layer 130-3, which includes the first common layer131, the third emissive layer 134, and the second common layer 135, byadjusting an angle of deposition and incidence at which a depositionmaterial discharged from a deposition source is incident toward thesubstrate 100. For example, the third opposite electrode 144 is formedto have a larger area than the third intermediate layer 130-3. Asdescribed above, because the third opposite electrode 143 completelycovers the third intermediate layer 130-3, damage to the thirdintermediate layer 130-3, which includes the third emissive layer 134,due to the first solvent used in a lift-off operation, which will befurther described later, may be prevented or substantially reduced.

Referring to FIG. 6F, the lift-off operation is performed on thestructure shown in FIG. 6D.

The third lift-off layer 163 is removed by using the second solventincluding fluorine.

After the lift-off operation, the third intermediate layer 130-3 and thethird opposite electrode 143 are left as patterns on the third pixelelectrode 103, the pixel defining layer 110, and the barrier layer 120,together with the patterns of the first intermediate layer 130-1 and thefirst opposite electrode 141 formed in the first unit process and thepatterns of the second intermediate layer 130-2 and the second oppositeelectrode 142 formed in the second unit process.

Referring to FIG. 7 , a common electrode 150 is formed on the structureshown in FIG. 6F. The common electrode 150 is integrally (e.g.,continuously) formed to cover all of the first through third oppositeelectrodes 141, 142, and 143.

The first emissive layer 132 emits light having a first color, thesecond emissive layer 133 emits light having a second color, and thethird emissive layer 134 emits light having a third color. For example,the first color may be red, the second color may be green, and the thirdcolor may be blue. A full-color organic light-emitting display devicemay be manufactured by the above-described first through third unitprocesses.

An encapsulation member encapsulating the organic light-emitting elementmay be further included on the common electrode 150. The encapsulationmember may be formed of a glass substrate, a metal foil, a thin filmencapsulation layer in which an inorganic layer and an organic layer aremixed or stacked, or the like.

In the illustrated embodiment, instead of depositing the patterns of thefirst intermediate layer 130-1 and the first opposite electrode 141, thesecond intermediate layer 130-2 and the second opposite electrode 142,and the third intermediate layer 130-3 and the third opposite electrode143 by using a fine metal mask as in conventional examples, thesepatterns are formed by using the above-described lift-off operations.Thus, misalignment between the substrate 100 and the fine metal mask maybe avoided because a fine metal mask is not needed. Thus, themanufacturing costs may be reduced.

In addition, in the illustrated embodiment, the first common layer 131is disconnected at the boundary between the barrier layer 120 and thepixel defining layer 110 in each pixel, and thus, flow of electrons fromthe first opposite electrode 141 to the first common layer 131 outsideof the pixel area is prevented or substantially reduced. Thereby,leakage current may be prevented or substantially reduced.

Hereinafter, an organic light-emitting display device 5 according to acomparative example which does not include the barrier layer having theundercut structure as in the above-described embodiments of the presentdisclosure will be described with reference to FIGS. 8A, 8B, and 9 .

FIGS. 8A and 8B are schematic cross-sectional views illustrating aprocess of manufacturing the organic light-emitting display device 5according to the comparative example, and FIG. 9 is an enlargedcross-sectional view of the portion IX of FIG. 8B.

FIG. 8A illustrates a first unit process of the comparative example inwhich a first lift-off layer 161 and a first photoresist 171, whichtogether form a first undercut structure, are used as a mask to deposita first intermediate layer 130-1, which includes a first common layer131, a first emissive layer 132, and a second common layer 135, on afirst pixel electrode 101 and a pixel defining layer 110.

The organic light-emitting display device 5 according to the comparativeexample does not include the barrier layer 120 (see, e.g., FIG. 1 )unlike the above-described embodiments of the present disclosure.

Because the first lift-off layer 161 and the first photoresist 171function as a mask, the first common layer 131, the first emissive layer132, and the second common layer 135 are not uniformly deposited onedges of a deposition area; they are instead deposited with a graduallydecreasing thickness on the pixel defining layer 110 towards the edgesof the deposition area.

FIG. 8B illustrates the first opposite electrode 141 that is formed onthe structure shown in FIG. 8A through vacuum deposition. The firstopposite electrode 141 is deposited to completely cover the firstintermediate layer 130-1 by controlling an angle of deposition andincidence of a deposition material discharged from a deposition sourcetoward the substrate 100.

When formed under the same or substantially similar depositionconditions as the first intermediate layer 130-1 and the first oppositeelectrode 141 of the above-described embodiments of the presentdisclosure, the first opposite electrode 141 of the comparative exampleis on the pixel defining layer 110 and contacts an edge 131-L of thefirst common layer 131 (see, e.g., FIG. 9 ), an edge 132-L of the firstemissive layer 132, and an edge 135-L of the second common layer 135.Electrons from the first opposite electrode 141 flow to the first commonlayer 131, the first emissive layer 132, and the second common layer 135through these contact areas and, particularly, to the first pixelelectrode 101 along the first common layer 131. Accordingly, leakagecurrent may be generated.

Ideally, current does not flow in the organic light-emitting devicebefore a driving voltage reaches a threshold voltage. However, in thecomparative example, electrons from the first opposite electrode 141flow to the first common layer 131 in a region where the first oppositeelectrode 141 and the first common layer 131 are in direct contact witheach other, and these electrons may flow to the first pixel electrode101 to generate leakage current.

According to embodiments of the present disclosure, the barrier layer120 arranged on the pixel defining layer 110 has the undercut structure,and thus, the first common layer 131 is disconnected at the boundarybetween the barrier layer 120 and the pixel defining layer 110. Thus,electrons from the first opposite electrode 141 do not flow to the firstcommon layer 131 outside of the pixel area. Accordingly, leakage currentmay be prevented or substantially reduced.

Hereinafter, other embodiments of the present disclosure will bedescribed with reference to FIGS. 10-12 . The description of thefollowing embodiments of the present disclosure will primarily focus ondifferences from the embodiments of the present disclosure describedabove.

FIG. 10 is a schematic cross-sectional view of a portion of an organiclight-emitting display device 2 according to an embodiment of thepresent disclosure.

Referring to FIG. 10 , the organic light-emitting display device 2includes a first pixel electrode 101 arranged on a substrate 100, apixel defining layer 110 having a first opening OP1 exposing a centerportion of the first pixel electrode 101, a barrier layer 120 arrangedon the pixel defining layer 110 and having a second opening OP2 that islarger than the first opening OP1 and having an undercut structure, afirst intermediate layer 130-1 arranged on the first pixel electrode101, the pixel defining layer 110, and the barrier layer 120, a firstopposite electrode 141 covering the first intermediate layer 130-1, anda common electrode 150 arranged on the first opposite electrode 141. Thebarrier layer 120 includes a first barrier layer 121 and a secondbarrier layer 122 having an undercut structure.

A total thickness D2 of the barrier layer 120 of this embodiment is lessthan a total thickness D1 of the barrier layer 120 described above inreference to FIG. 1 . The total thickness D2 of the barrier layer 120 isgreater than a thickness D130-1 of the first intermediate layer 130-1.

When the first intermediate layer 130-1 and the first opposite electrode141 are deposited under the same or substantially similar conditions asin the embodiment illustrated in FIG. 1 , the first common layer 131 andthe first emissive layer 132 are disconnected at the boundary betweenthe barrier layer 120 and the pixel defining layer 110, and the secondcommon layer 135 and the first opposite electrode 141 are connected atthe boundary between the barrier layer 120 and the pixel defining layer110.

Similar to the embodiment shown in FIG. 1 , the first common layer 131of the embodiment illustrated in FIG. 10 is disconnected at the boundarybetween the barrier layer 120 and the pixel defining layer 110, andthus, electrons from the first opposite electrode 141 do not flow to thefirst common layer 131 outside the pixel area. Accordingly, leakagecurrent may be prevented or substantially reduced.

FIG. 11 is a schematic cross-sectional view of a portion of an organiclight-emitting display device 3 according to an embodiment of thepresent disclosure.

Referring to FIG. 11 , the organic light-emitting display device 3includes a first pixel electrode 101 arranged on a substrate 100, apixel defining layer 110 having a first opening OP1 exposing a centerportion of the first pixel electrode 101, a barrier layer 120 arrangedon the pixel defining layer 110 and having a second opening OP2 that islarger than the first opening OP1 and having an undercut structure, afirst intermediate layer 130-1 arranged on the first pixel electrode101, the pixel defining layer 110, and the barrier layer 120, a firstopposite electrode 141 covering the first intermediate layer 130-1, anda common electrode 150 arranged on the first opposite electrode 141. Thebarrier layer 120 in this embodiment has a single-layer undercutstructure.

A total thickness D3 of the barrier layer 120 in the embodimentillustrated in FIG. 11 is less than a total thickness D1 of the barrierlayer 120 of the embodiment illustrated in FIG. 1 . In addition, thetotal thickness D3 of the barrier layer 120 illustrated in FIG. 11 isless than a thickness D130-1 of the first intermediate layer 130-1.However, the total thickness D3 of the barrier layer 120 illustrated inFIG. 11 is greater than a thickness D131 of the first common layer 131.

When the first intermediate layer 130-1 and the first opposite electrode141 are deposited under the same or substantially similar conditions asin the embodiment illustrated in FIG. 1 , the first common layer 131 isdisconnected at the boundary between the barrier layer 120 and the pixeldefining layer 110 and the first emissive layer 132, the second commonlayer 135, and the first opposite electrode 141 are connected at theboundary between the barrier layer 120 and the pixel defining layer 110.

However, because the first common layer 131 is disconnected at theboundary between the barrier layer 120 and the pixel defining layer 110in the embodiment illustrated in FIG. 11 , similar to the embodimentillustrated in FIG. 1 , electrons do not flow from the first oppositeelectrode 141 to the first common layer 131 outside the pixel area.Accordingly, leakage current may be prevented or substantially reduced.

FIG. 12 is a schematic cross-sectional view of an organic light-emittingdisplay device 4 according to an embodiment of the present disclosure.

Referring to FIG. 12 , the organic light-emitting display device 4includes a first pixel electrode 101 arranged on a substrate 100, apixel defining layer 110 having a first opening OP1 exposing a centerportion of the first pixel electrode 101, a first intermediate layer130-1 arranged on the first pixel electrode 101 and the pixel defininglayer 110, a first opposite electrode 141 covering the firstintermediate layer 130-1, and a common electrode 150 arranged on thefirst opposite electrode 141.

Different from the above-described embodiments of the presentdisclosure, no barrier layer is included in the embodiment shown in FIG.12 and the pixel defining layer 110 having an undercut structure isincluded.

A thickness D110 of the pixel defining layer 110 in the embodimentillustrated in FIG. 12 is less than the total thickness D1 of thebarrier layer 120 of the embodiment illustrated in FIG. 1 . In addition,the thickness D110 of the pixel defining layer 110 in the embodimentillustrated in FIG. 12 is less than a thickness D130-1 of the firstintermediate layer 130-1. However, the thickness D110 of the pixeldefining layer 110 in the embodiment illustrated in FIG. 12 is greaterthan the thickness D131 of the first intermediate layer 130-1.

When the first intermediate layer 130-1 and the first opposite electrode141 are deposited under the same or substantially similar conditions asin the embodiment illustrated in FIG. 1 , the first common layer 131 andthe first emissive layer 132 are disconnected at the boundary betweenthe barrier layer 120 and the pixel defining layer 110 and the secondcommon layer 135 and the first opposite electrode 141 are connected atthe boundary between the barrier layer 120 and the pixel defining layer110.

Because the first common layer 131 is disconnected at the boundarybetween the barrier layer 120 and the pixel defining layer 110, similarto the embodiment illustrated in FIG. 1 , electrons do not flow from thefirst opposite electrode 141 to the first common layer 131 outside thepixel area. Accordingly, leakage current may be prevented orsubstantially reduced.

According to embodiments of the present disclosure, an intermediatelayer including an emissive layer is formed by using a lift-offoperation instead of depositing the same by using a fine metal mask, andthus, misalignment of the fine metal mask may be avoided andmanufacturing costs may be reduced. In addition, by forming a barrierlayer having an undercut structure on a pixel defining layer or byforming a pixel defining layer having an undercut structure, a holeinjection layer at a boundary between the barrier layer and the pixeldefining layer may be disconnected from itself, thereby preventing orsubstantially reducing leakage current.

According to embodiments of the present disclosure, an intermediatelayer including an emissive layer is formed by using a lift-offoperation instead of by depositing the same by using a fine metal mask,and thus, misalignment of the fine metal mask may be avoided andmanufacturing costs may be reduced.

In addition, according to embodiments of the present disclosure, byforming a barrier layer having an undercut structure on a pixel defininglayer or by forming a pixel defining layer having an undercut structure,a hole injection layer at a boundary between the barrier layer and thepixel defining layer may be disconnected from itself, thereby preventingor substantially reducing leakage current.

It should be understood that the example embodiments of the presentdisclosure described herein should be considered in a descriptive senseand not for purposes of limitation. Descriptions of features and/oraspects within each embodiment should typically be considered asavailable for other similar features or aspects in other embodiments.

While embodiments of the present disclosure have been described withreference to the figures, it will be understood by those of ordinaryskill in the art that various changes in form and details may be madetherein without departing from the spirit and scope of the presentdisclosure as defined by the following claims and their equivalents.

What is claimed is:
 1. An organic light-emitting display devicecomprising: a substrate; a pixel electrode on the substrate; a pixeldefining layer having a first opening exposing a center portion of thepixel electrode; a barrier layer on the pixel defining layer, thebarrier layer having a second opening that is larger than the firstopening and having an undercut structure in which an edge of a topsurface of the barrier layer protrudes from an edge of a bottom surfaceof the barrier layer in a direction parallel to the substrate; anintermediate layer comprising a first common layer, a first emissivelayer, and a second common layer sequentially arranged on the pixelelectrode, the pixel defining layer, and the barrier layer; and a commonelectrode covering the intermediate layer, wherein portions of thecommon electrode, which are arranged on the pixel electrode, the pixeldefining layer, and the barrier layer, are connected to each other,wherein portions of the first common layer are disconnected from eachother at the undercut structure, and wherein the intermediate layercontacts a sidewall of the barrier layer below the undercut structure,an underside of the undercut structure being at an angle relative to thesidewall.
 2. The organic light-emitting display device of claim 1,wherein the pixel defining layer continuously surrounds an edge of thepixel electrode.
 3. The organic light-emitting display device of claim1, wherein portions of the second common layer are disconnected fromeach other at the undercut structure.
 4. The organic light-emittingdisplay device of claim 1, wherein portions of the first emissive layerare disconnected from each other at the undercut structure.
 5. Theorganic light-emitting display device of claim 1, wherein portions ofthe second common layer are disconnected from each other at the undercutstructure, and portions of the first emissive layer are disconnectedfrom each other at the undercut structure.
 6. The organic light-emittingdisplay device of claim 1, wherein a thickness of the barrier layer isgreater than a thickness of the intermediate layer.
 7. The organiclight-emitting display device of claim 1, wherein a thickness of thebarrier layer is greater than a thickness of the first common layer. 8.The organic light-emitting display device of claim 1, wherein athickness of the barrier layer is greater than a thickness of the secondcommon layer.
 9. The organic light-emitting display device of claim 1,wherein a thickness of the barrier layer is greater than a thickness ofthe first emissive layer.
 10. The organic light-emitting display deviceof claim 1, wherein the common electrode completely covers theintermediate layer.
 11. The organic light-emitting display device ofclaim 1, wherein the barrier layer comprises an organic material.
 12. Anorganic light-emitting display device comprising: a substrate; a pixelelectrode on the substrate; a pixel defining layer having a firstopening exposing a center portion of the pixel electrode; a barrierlayer on the pixel defining layer, the barrier layer comprising a bottomsurface contacting the pixel defining layer, a top surface having anedge protruding from an edge of the bottom surface in a directionparallel to the substrate to define an undercut structure, and aconnection surface connecting the edge of bottom surface and the edge oftop surface; an intermediate layer comprising a first common layer, afirst emissive layer, and a second common layer sequentially arranged onthe pixel electrode, the pixel defining layer, and the barrier layer;and a common electrode covering the intermediate layer, wherein portionsof the common electrode, which are arranged on the pixel electrode, thepixel defining layer, and the barrier layer, are connected to eachother, wherein portions of the first common layer are disconnected fromeach other at the connection surface of the barrier layer, and whereinthe intermediate layer contacts a sidewall of the barrier layer belowthe undercut structure, an underside of the undercut structure being atan angle relative to the sidewall.
 13. The organic light-emittingdisplay device of claim 12, wherein the first emissive layer isdisconnected at the connection surface of the barrier layer.
 14. Theorganic light-emitting display device of claim 13, wherein the secondcommon layer is disconnected at the connection surface of the barrierlayer.
 15. The organic light-emitting display device of claim 12,wherein the barrier layer comprises a second opening that is larger thanthe first opening.
 16. The organic light-emitting display device ofclaim 12, wherein the pixel defining layer continuously surrounds anedge of the pixel electrode.
 17. The organic light-emitting displaydevice of claim 12, wherein a thickness of the barrier layer is greaterthan a thickness of the intermediate layer.
 18. The organiclight-emitting display device of claim 12, wherein the common electrodecompletely covers the intermediate layer.
 19. The organic light-emittingdisplay device of claim 12, wherein the barrier layer comprises anorganic material.